Concrete Earth ECOGUARD™ Pre-Grind is a water based concentrated, non-hazardous biodegradable cleaning and etching compound. It is formulated for preparing concrete surfaces for easier grinding using higher grit metal diamonds on the first cut to obtain a quick and clean exposed Salt n' Pepper surface, or a clean Cream polish finish using low grit resin diamond abrasives. ECOGUARD™ Pre-Grind is formulated using organic acids and surfactants made from naturally occurring materials, which makes it safer to use and just as effective as traditional hydrochloric or phosphoric based solutions.